diff options
| author | Alan Somers <asomers@FreeBSD.org> | 2016-05-23 20:29:18 +0000 |
|---|---|---|
| committer | Alan Somers <asomers@FreeBSD.org> | 2016-05-23 20:29:18 +0000 |
| commit | 1b82e02f4d91dc0942e754fa6c08042537f13980 (patch) | |
| tree | 75b6884b5df8b2102bd857790de587c4b853854d /UPDATING | |
| parent | fc13dfc8e2bc8797356e7d85bf71183d356824e8 (diff) | |
| download | src-test-1b82e02f4d91dc0942e754fa6c08042537f13980.tar.gz src-test-1b82e02f4d91dc0942e754fa6c08042537f13980.zip | |
Add bit_count to the bitstring(3) api
Add a bit_count function, which efficiently counts the number of bits set in
a bitstring.
sys/sys/bitstring.h
tests/sys/sys/bitstring_test.c
share/man/man3/bitstring.3
Add bit_alloc
sys/kern/subr_unit.c
Use bit_count instead of a naive counting loop in check_unrhdr, used
when INVARIANTS are enabled. The userland test runs about 6x faster
in a generic build, or 8.5x faster when built for Nehalem, which has
the POPCNT instruction.
sys/sys/param.h
Bump __FreeBSD_version due to the addition of bit_alloc
UPDATING
Add a note about the ABI incompatibility of the bitstring(3)
changes, as suggested by lidl.
Suggested by: gibbs
Reviewed by: gibbs, ngie
MFC after: 9 days
X-MFC-With: 299090, 300538
Relnotes: yes
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D6255
Notes
Notes:
svn path=/head/; revision=300539
Diffstat (limited to 'UPDATING')
| -rw-r--r-- | UPDATING | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/UPDATING b/UPDATING index fd47ac042b799..df0542dfab3c6 100644 --- a/UPDATING +++ b/UPDATING @@ -31,6 +31,12 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW: disable the most expensive debugging functionality run "ln -s 'abort:false,junk:false' /etc/malloc.conf".) +20160523: + The bitstring(3) API has been updated with new functionality and + improved performance. But it is binary-incompatible with the old API. + Objects built with the new headers may not be linked against objects + built with the old headers. + 20160520: The brk and sbrk functions have been removed from libc on arm64. Binutils from ports has been updated to not link to these |